The Facts

Each year, participation in sports or exercise accounts for approximately 35% of injuries that occur in Canada.

People who participate in sports are more likely than others of the same age to have muscle and tendon injuries and bone fractures. This certainly doesn't mean you should avoid sports - the health benefits far outweigh the cost in terms of sports injuries.

Causes

Sports injuries are most commonly caused by poor training methods; structural abnormalities; weakness in muscles, tendons, ligaments; and unsafe exercising environments. The most common cause of injury is poor training. For example, muscles need 48 hours to recover after a workout. Increasing exercise intensity too quickly and not stopping when pain develops while exercising also causes injury.

Everyone's bone architecture is a little different, and almost all of us have one or two weak points where the arrangement of bone and muscle leaves us prone to injury. Common predisposing factor in injuries to the ankles, legs, knees, and hips include:

uneven leg length

excessive pronation (flat feet)

cavus foot (over-high arches)

bowlegged or knock-knee alignment

Uneven leg length may lead to awkward running and increases the chance of injury, but many people with equal-length legs suffer the same effects by running on tilted running tracks or along the side of a road that is higher in the centre. The hip of the leg that strikes the higher surface will suffer more strain.

Pronation is the inward rolling of the foot after the heel strikes the ground, before the weight is shifted forward to the ball of the foot. By rolling inwards, the foot spreads the shock of impact with the ground. If it rolls too easily, however, it can place uneven stress on muscles and ligaments higher in the leg.

While an overly flexible ankle and foot can cause excessive pronation, a too-rigid ankle will cause the effects of cavus foot. Although the arch of the foot itself may be normal, it appears very high because the foot doesn't flatten inwards when weight is placed on it. Such feet are poor shock absorbers and increase the risk of fractures higher in the legs.

Bowlegs or knock knees add extra stress through knees and ankles over time, and may make ankle sprains more likely.

Other structural conditions that make sports injuries more common include:

lumbar lordosis: forward curve in the lower spine

patella alta: a kneecap that's higher than usual

high Q angle: kneecap displaced to one side, as with knock knees

Having some muscles that are very strong and others that are weak can lead to injury. If your quadriceps (front thigh muscles) are very strong, it can increase the risk of a stretched or torn hamstring (rear thigh muscle). Tight iliotibial bands may be the cause of knee pain for many athletes in running sports.

Overuse injuries are caused by repeated, microscopic injuries to a part of the body. Many long distance runners experience overuse injuries even after years of running. For road runners, the surface is hard and sometimes uneven, and the running movements are repetitive. In addition, there are usually both up- and downhill elements, and these increase the stress on tendons and muscles in the lower leg. You will more likely develop running injuries if you wear the wrong shoes or sneakers. You should use footwear that doesn't allow side-to-side movement of the heel, and that adequately cushions the foot.

People who play racquet sports tend to injure their upper body. The need to firmly grasp the racquet and the shock of impact with the ball can cause various injuries to the tendons of the wrist and elbow, such as "tennis elbow," which may extend into the muscles of the forearm. In addition, the human arm really isn't designed to handle strenuous activity above the head. Tennis is a leading cause of rotator cuff (shoulder joint) tendinitis. This is potentially one of the most difficult sports injuries. If you continue to play tennis when you have a sore shoulder, the rotator cuff tendons can fray or tear and may require surgery.

Symptoms and Complications

There are several common sports injuries.

Shin splints: Shin splints have a number of causes and may occur on the outside or the inside of the shin. With anterolateral shin splints, pain around the front of the shin starts immediately when your heel strikes the ground awkwardly. In posteromedial shin splints, the pain is felt on the inner part of the shins and is worse when you stand on your toes. If you keep running on a regular basis when you have a shin splint, the pain tends to spread toward the knee. Tests are often required to understand the exact nature and cause of shin splints.

Achilles tendinitis: The Achilles tendon (the tough sinew that attaches the calf muscle to the back of the heel bone) is most likely to be damaged if you participate in running or jumping sports. The injured Achilles tendon feels tender when squeezed between the fingers. Pain is usually at its worst in the morning and improves with walking. Vigorous exercise will increase the pain for a bit, then improve it. However, you should never exercise a damaged Achilles tendon without the supervision of a sport medicine physician or therapist, or until it's healed.

Lumbar strain: The standard weightlifter's injury can also occur in sports that involve sudden twisting of the back, such as golf and baseball. Sudden lower back pain appears with twisting or lifting. It may seem fairly minor for an hour or two, but carrying on the exercise will usually bring a sudden deterioration with extreme pain and back spasms.

Lateral and medial epicondylitis: More commonly known as backhand and forehand tennis elbow. Backhand tennis elbow can also occur with overuse of a screwdriver, but tennis may be more problematic because not only are you gripping hard, but there are also repetitive shocks being transmitted to the flexed wrist tendons. Forehand tennis elbow is also common in golfers, baseball players, and people who have to lug heavy suitcases around. You feel pain when you flex the wrist backward (lateral tendons) or forward (medial tendons).

Metatarsal stress fracture: The second to fourth toes are vulnerable to breakage if you push off with your toes when sprinting or running long distances. Army cadets doing running and marching drills are likely to suffer stress fractures during training camps. Dancers and gymnasts experience stress fractures because of frequent jumping. The front of the foot starts hurting during exercise, and the pain usually stops when you finish. With each subsequent bout of exercise, the pain appears earlier and earlier, and gets steadily worse. The fracture can take up to 3 months to fully heal.

Any injured tendon can undergo permanent changes if you continue to exercise it without letting it heal. The normal tendon material can be replaced with inflexible fibrous material in a process called mucoid degeneration. The ligament attaching it to the bone can tear, there may be steady bleeding, and the bone can even change shape where it meets the tendon, forming a spur that may cause pain on movement. In the worst-case scenario, pain can become constant whether you're moving or not, and the affected parts become permanently weak.

It's vital to follow doctor's advice about rest. If you cannot see a doctor, don't exercise the affected area until you're sure it's healing.

Making the Diagnosis

Your own description of what happened normally makes the nature of the injury fairly clear to a doctor or sports injury specialist. There are also a number of standard tests for sports injuries; they all involve flexing the joint or tendon in question. In tennis elbow, for example, you are asked to place your forearm on a table and to flex your wrist forwards or backwards while the doctor restrains your hand. Depending on the nature of the injury, there's the option of X-rays and other scans, but these are usually only necessary in severe injuries and fractures.

Treatment and Prevention

Treatment of sports injuries is based on the RICE principle:

Rest

Ice

Compression

Elevation

Rest stops new injury and bleeding. Ice eases pain and reduces inflammation by constricting the blood vessels. Elevation and compression limit the amount of swelling and fluid accumulation around the injured area.

Ice should be crushed to better conform to your shape. It should be placed in a bag that is wrapped around the injury. First, put a towel between the bag and the skin. Then, wrap a bandage around the icebag, not so tight as to cut off blood flow. Ice only constricts blood vessels for about 10 minutes, after which they "rebound." For very new or traumatic injuries you should leave the ice in place for only 10 minutes at a time, removing it for the same period. Alternate like this for an hour or two, keeping the injury elevated all the time.

You should carry out this procedure several times during the first day or so after injury. Following this, ice can be used for longer periods to better reduce swelling and pain. You can apply ice for up to 30 minutes several times a day. Packages of frozen peas or corn are excellent ready-made ice packs. If the injury is in the leg or ankle, don't try to stand up the first day, and do your best to keep it elevated as much as possible.

There is also some evidence for using chiropractic techniques, such as manipulative therapy and full kinetic chain or exercise therapy, to help manage ankle sprains.

If there's some other exercise you can perform that doesn't stress your injured part, you can do that to remain fit, but don't try to use the injured part until healing is well along. Then you can start light exercises to get it back in shape. In the long run, you may want to exercise it more to make it stronger, in order to prevent repeat occurrences. A doctor or physiotherapist might recommend specific exercises to strengthen particular muscles and tendons.

Other treatments include surgery and steroid injections. Surgery is an extreme measure and one you're unlikely to need if you treat injuries with respect. Steroid injections can relieve pain but may delay healing. They can be safely used once or twice, but should never be used as a cure-all or a first resort.

There are two ways you can prevent sports injuries. One is by using the right equipment. This means properly-fitting, sport-specific shoes and may mean orthotics (shoe inserts) to control excessive movement of the foot. Orthotics may reduce the width of your footwear, so you may need new shoes. Helmets, face masks, and protective padding made to regulation and worn as instructed prevent many serious sport injuries.

Correct technique is important to prevent injury. For example, tennis players should avoid racquets with excessively narrow shafts and try to perform backhand and forehand shots with their whole arm and shoulder rather than just the wrist. Racquet strings shouldn't be too tight. Wet, heavy balls are more likely to cause problems, as is hitting the ball off-centre.

The second way of preventing injury is by warming up and cooling down with adequate stretching. The best medical evidence suggests that warming up definitely makes the muscles stronger and more injury resistant. Stretching improves muscle performance but not injury resistance, so it is most effective after exercise. Don't stretch so far that it becomes painful. Cooling down may help prevent dizziness from blood pooling in dilated (widened) leg veins, but it doesn't help muscle soreness the next day, which is caused by injury to the fibres.

All strenuous exercise involves microscopic damage to individual muscle fibres. Exercise works because they tend to heal stronger than before. You must give them 48 hours to heal. You shouldn't vigorously exercise the same muscle in two successive days, as you'll be damaging it faster than it can heal. If you want to exercise every day, you should either work on different muscle groups on alternate days or do "strength-training" exercises one day and cardiovascular exercises the next. Following these recommendations should allow you to enjoy regular and injury-free exercise.